Signal processing device, signal processing method, signal processing program, and image capture device

ABSTRACT

A signal processing device, on the basis of an image capture signal acquired by an image capture device provided with an anamorphic lens, performs a detection process each in a vertical direction of the anamorphic lens and in a horizontal direction of the anamorphic lens.

TECHNICAL FIELD

The present technology relates to a signal processing device, a signalprocessing method, a signal processing program, and an image capturedevice.

BACKGROUND ART

A general camera lens is designed to be optically symmetrical in therotation direction with respect to the lens optical axis. However, forexample, a special lens such as an anamorphic lens used for cinemaphotography or the like is intentionally designed to have differentoptical characteristics in the horizontal and vertical directions.

An anamorphic lens is a lens that has different optical characteristics(focal length) in the vertical and horizontal directions. Generally, theanamorphic lens is designed so that the focal length in the horizontaldirection is short, and an image is recorded in a state that the imageis compressed in the horizontal direction when imaging. Then, bystretching the image in the horizontal direction when reproducing theimage, it is possible to reproduce a horizontally long natural imagebeing equal to or larger than an aspect of a recording element.

However, since the focal lengths are different between the vertical andhorizontal directions, the depth of field changes between the verticaland horizontal directions, so there is a problem that focusing cannot bedone like the general lens that is optically symmetric in the rotationdirection with respect to the lens optical axis.

Therefore, a method that uses two focus lenses, one is a spherical lens(image plane positions in the vertical and horizontal directions movesimultaneously), and the other is a cylindrical lens (only an imageplane position either in the vertical or horizontal direction moves),has been proposed (Patent Document 1).

CITATION LIST Patent Document

-   Patent Document 1: Japanese Patent Application Laid-Open No.    H6-14239

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

However, the method described in Patent Document 1 uses a movable lens34 and a focusing lens 20 as two lenses and realizes focusing by atwo-step operation of operating the focusing lens 20 and then operatingthe movable lens 34. From the viewpoint of autofocus speed, it isinefficient to adjust the focus in such two steps.

The present technology has been made in view of such points, and anobject of the present technology is to provide a signal processingdevice, a signal processing method, a signal processing program, and animage capture device, in which it is possible for also an image capturedevice provided with an anamorphic lens to perform processing related tofocus adjustment appropriately.

Solutions to Problems

In order to solve the problems described above, the first technology isa signal processing device that, on the basis of an image capture signalacquired by an image capture device provided with an anamorphic lens,performs a detection process each in the vertical direction of theanamorphic lens and in the horizontal direction of the anamorphic lens.

Also, the second technology is a signal processing method includingperforming a detection process, on the basis of an image capture signalacquired by an image capture device provided with an anamorphic lens,each in the vertical direction of the anamorphic lens and in thehorizontal direction of the anamorphic lens.

Also, the third technology is a signal processing program for, on thebasis of an image capture signal acquired by an image capture deviceprovided with an anamorphic lens, causing a computer to execute a signalprocessing method including performing a detection process each in thevertical direction of the anamorphic lens and in the horizontaldirection of the anamorphic lens.

Furthermore, the fourth technology is an image capture device includingan anamorphic lens, an image capture element provided with a pluralityof phase difference detection pixels arranged to make placementdensities different between a direction corresponding to a verticaldirection of the anamorphic and a direction corresponding to ahorizontal direction orthogonal to the vertical direction of theanamorphic lens, and a signal processing unit that performs a detectionprocess each in the vertical direction of the anamorphic lens and in thehorizontal direction of the anamorphic lens on the basis of an imagecapture signal acquired by the image capture element.

Effects of the Invention

According to the present technology, also in an image capture deviceprovided with an anamorphic lens, it is possible to perform processingrelated to focus adjustment appropriately. Note that the effectsdescribed in the present disclosure are not necessarily limited, and theeffects described in the present disclosure may be any of the effectsdescribed in the specification.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating a configuration of an imagecapture device according to a first embodiment.

FIG. 2 is a graph illustrating an example of modulation transferfunction (MTF) characteristics in an anamorphic lens.

FIG. 3 is an explanatory diagram of a phase difference detection pixel.

FIG. 4 is an explanatory diagram of a first aspect of autofocus control.

FIG. 5 is a diagram illustrating selection of an autofocus method to beused.

FIG. 6 is an explanatory diagram of a second aspect of the autofocuscontrol.

FIG. 7 is a flowchart illustrating a flow of lens stopping process.

FIG. 8 is a diagram illustrating a configuration of an image captureelement according to the first embodiment.

FIG. 9 is an explanatory diagram of an exit pupil distance according tothe first embodiment.

FIG. 10 is a block diagram illustrating a configuration of an imagecapture device according to a second embodiment.

FIG. 11 is a block diagram illustrating a configuration of a peakingprocessing unit.

FIG. 12 is an explanatory diagram of peaking drawing.

FIG. 13 is an explanatory diagram of peaking drawing.

FIG. 14 is a block diagram illustrating a configuration of an imagecapture device according to a third embodiment.

FIG. 15 is a flowchart illustrating a process of a first aspect of afocus adjustment process of the third embodiment.

FIG. 16 is a flowchart illustrating a process of a second aspect of thefocus adjustment process of the third embodiment.

MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present technology will be describedwith reference to the drawings. Note that the description will be givenin the following order.

<1. First embodiment>

[1-1. Configuration of image capture device]

[1-2. About MTF characteristic in anamorphic lens]

[1-3. Processing in signal processing device]

[1-4. Processing of driving and stopping lens]

[1-5. Configuration of image capture element]

<2. Second embodiment>

[2-1. Configuration of image capture device]

[2-2. Peaking process]

<3. Third embodiment>

[3-1. Configuration of image capture device]

[3-2. First focus adjustment process by signal processing device: finefocus adjustment]

[3-3. Second focus adjustment process by signal processing device: focusbracket imaging]

<4. Modification example>

First Embodiment

[1-1. Configuration of Image Capture Device]

First, a configuration of an image capture device 100 including a signalprocessing device 150 according to a first embodiment will be describedwith reference to FIG. 1. In the first embodiment, in the image capturedevice 100 provided with an anamorphic lens 101, an in-focus position isdetermined by a detection process, and an autofocus control is performedon the basis of the in-focus position. Note that detection in a case ofimage plane phase-detection autofocus (AF) is to detect the phasedifference, and detection in a case of contrast detection AF is todetect a contrast.

The image capture device 100 includes an optical image capture system102 including the anamorphic lens 101, a lens driver 103, an imagecapture element 104, a signal processing large-scale integration (LSI)105, an image signal processing unit 106, a codec unit 107, a storageunit 108, a display control unit 109, a display unit 110, an input unit111, a control unit 112, a detection unit 113, a signal processingdevice 150, an in-focus position determination unit 151, and anautofocus (AF) control unit 152.

The optical image capture system 102 includes the anamorphic lens 101for concentrating light from a subject on the image capture element 104,a drive mechanism for zooming, a shutter mechanism, an iris mechanism,and the like. These are driven on the basis of a control signal from thecontrol unit 112 and the lens driver 103. An optical image of thesubject obtained through the optical image capture system 102 is formedon the image capture element 104 as an image capture component.

The lens driver 103 includes, for example, a microcomputer and the like,and controls operations such as driving of the anamorphic lens 101 forautofocus, the drive mechanism of the optical image capture system 102,the shutter mechanism, the iris mechanism, and the like in accordancewith a control of the control unit 112. Accordingly, an exposure time (ashutter speed), an aperture value (an F value), and the like areadjusted.

The image capture element 104 photoelectrically converts the incidentlight from the subject into an electric charge amount and outputs as ananalog image capture signal. The analog image capture signal output fromthe image capture element 104 is output to the image signal processingunit 106. As the image capture element 104, a charge-coupled device(CCD), a complementary metal-oxide semiconductor (CMOS), or the like isused.

The image signal processing unit 106, with respect to the image capturesignal output from the image capture element 104, performs a sample holdby a correlated double sampling (CDS) processing for maintaining a goodsignal/noise (S/N) ratio, an auto gain control (AGC) processing, ananalog/digital (A/D) conversion, and the like, and generates an imagesignal.

Also, the image signal processing unit 106 may perform predeterminedsignal processing such as demosaicing processing, white balanceadjustment processing, color correction processing, gamma correctionprocessing, Y/C conversion processing, auto exposure (AE) processing,resolution conversion processing on an image signal.

The codec unit 107 performs coding processing for recording orcommunication, for example, on the image signal that has been subjectedto the predetermined processing.

The storage unit 108 is a large-capacity storage medium, for example,such as a hard disk, a memory stick (registered trademark of SonyCorporation), an SD memory card, and the like. An image is saved in acompressed state on the basis of standards, for example, such as JointPhotographic Experts Group (JPEG) and the like. Also, Exchangeable ImageFile Format (EXIF) data including information regarding the saved imageand additional information such as imaging date and time and the like isalso saved in association with the image. A moving image is saved informats, for example, such as Moving Picture Experts Group 2 (MPEG-2),MPEG-4, and the like.

The display control unit 109 controls displaying generated image data onthe display unit.

The display unit 110 is, for example, a display device including aliquid crystal display (LCD), a plasma display panel (PDP), an organicelectroluminescence (EL) panel, or the like. The display unit 110displays a user interface of the image capture device 100, a menuscreen, a monitoring image during image capture, a captured imagerecorded in the storage unit 108, a captured moving image, and the like.

The input unit 111 includes, for example, a power button for switchingbetween power on and power off, a release button for instructing tostart recording an image, a zoom lever for adjusting zoom, a touchscreen integrated with the display unit 110, and the like. Whenperforming an input on the input unit 111, a control signalcorresponding to the input is generated and output to the control unit112. Then, the control unit 112 performs an arithmetic processing andcontrol corresponding to the control signal.

The control unit 112 includes a central processing unit (CPU), a randomaccess memory (RAM), a read-only memory (ROM), and the like. The ROMstores a program and the like that is read and executed by the CPU. TheRAM is used as a work memory of the CPU. The CPU controls the entireimage capture device 100 by executing various processes according to theprogram stored in the ROM and issuing commands.

The detection unit 113 uses the supplied image capture signal to performthe detection process in each of the vertical and horizontal directionsof the image, determines an in-focus position of the subject in adetection range for autofocus, and acquires an amount of defocus in alldetection range. The amount of defocus is an amount of deviation fromthe focal point. Furthermore, the detection unit 113 acquires an MTFcorresponding to the amount of defocus and generates detectioninformation including the amount of defocus and the MTF as illustratedin FIG. 2. The detection information acquired by the detection unit 113is supplied to the in-focus position determination unit 151. It shouldbe noted that the vertical and horizontal directions of the imagecorrespond to the vertical and horizontal directions of the anamorphiclens 101, respectively, and the vertical and horizontal directions areassumed to be orthogonal to each other.

The signal processing device 150 includes the in-focus positiondetermination unit 151 and the AF control unit 152.

The in-focus position determination unit 151 determines the in-focusposition of autofocus on the basis of the detection information suppliedfrom the detection unit 113. A difference of focus to an in-focusposition of the anamorphic lens 101 is an amount of focus deviation. Thefarther the position of the anamorphic lens 101 is from the in-focusposition, the larger the amount of focus deviation, and the closer theposition of the anamorphic lens 101 is to the in-focus position, thesmaller the amount of focus deviation. Details of the processing by thein-focus position determination unit 151 will be described later. Thedetermined in-focus position information is supplied to the AF controlunit 152.

By driving the lens driver 103 on the basis of the in-focus positioninformation supplied from the in-focus position determination unit 151,the AF control unit 152 performs autofocus control to move theanamorphic lens 101 by a predetermined amount along the optical axisdirection to focus on the subject.

Note that the signal processing device 150 includes a program, and theprogram may be installed in the image capture device 100 preliminarilyor may be distributed by download, storage medium, or the like so thatthe user can install the program by himself/herself. Note that thesignal processing device 150 is not only realized by a program, but mayalso be realized by combining a dedicated device, a circuit, or the likeby hardware having the function.

The image capture device 100 is configured as described above.

[1-2. About MTF Characteristic in Anamorphic Lens]

Next, MTF characteristics of the anamorphic lens 101 will be described.FIG. 2 is a graph illustrating an example of modulation transferfunction (MTF) characteristics in the anamorphic lens 101. MTF is one ofthe indexes for evaluating the performance of a lens and indicates as aspatial frequency characteristic how faithfully the contrast of thesubject can be reproduced in order to know an image formationperformance of the lens. The MTF at a specific spatial frequencycorresponds to a resolution and indicates that the larger the value, thehigher the resolution. In FIG. 2, the horizontal axis indicates aparaxial ray position of the optical system in the horizontal direction.Also, the vertical axis indicates the MTF. In FIG. 2, a solid lineindicates the MTF characteristics in the horizontal direction, and abroken line indicates the MTF characteristics in the vertical direction.Also, MTF characteristics at Fl (low frequency) are illustrated by athick line, and MTF characteristics at Fh (high frequency) areillustrated by a thin line.

The anamorphic lens 101 generally has a shorter focal length and agreater depth of field, in the horizontal direction than in the verticaldirection. As a result, in a case where the horizontal axis of the graphin FIG. 2 is the amount of defocus, there is a feature that the MTFcharacteristic is less likely to decrease in the horizontal directioneven if the amount of defocus is the same in the vertical and horizontaldirections. Also, it is possible to mention that the inclination of theMTF characteristic differs between the vertical and horizontaldirections. Therefore, it is possible to mention that an image isblurred faster in the vertical direction compared to the horizontaldirection. As a result, even with the same amount of defocus, in thevertical direction compared to the horizontal direction, the MTF tendsto decrease so that the image looks blurred. Also, it is possible tomention that a range of the amount of defocus, which is regarded to bein focus, is wider in the horizontal direction compared to the verticaldirection.

Furthermore, a peak position of the MTF characteristic differs betweenthe vertical and horizontal directions. While up to depend on theoptical design, it is difficult to match the peak positions of the MTFcharacteristics between the vertical and horizontal directions under allconditions. Note that the MTF characteristics between the vertical andhorizontal directions also change depending on a frequency of thesubject. Note that it is assumed that the vertical direction and thehorizontal direction are orthogonal to each other.

Normally, detection in autofocus is performed in the horizontaldirection. However, in the anamorphic lens 101, since the inclination ofthe MTF characteristic differs between the vertical and horizontaldirections, if detection is performed only in the horizontal direction,autofocus in the vertical direction does not function normally.

[1-3. Processing in Signal Processing Device]

Next, by the signal processing device 150 including the in-focusposition determination unit 151 and the AF control unit 152, anautofocus control in the image capture device 100 including theanamorphic lens 101 will be described. Note that, in the followingdescription being made, autofocus shall be image plane phase-detectionAF.

FIG. 4 is a diagram illustrating a configuration of a general phasedifference detection pixel for performing image plane phase-detectionAF. FIG. 4A illustrates a first phase difference detection pixel A, FIG.4B illustrates a second phase difference detection pixel B, and FIG. 4Cis a diagram illustrating an arrangement of pixels in the image captureelement 104.

The first phase difference detection pixel A includes a light-receivingelement 11. Also, a microlens 12 is provided on an incident side of thelight. Furthermore, a light-shielding layer 13 that blocks incidentlight is provided between the light-receiving element 11 and themicrolens 12 in order to perform pupil division. The light-shieldinglayer 13 has an opening 14 eccentric to one side direction with respectto the center of the light-receiving element 11. The first phasedifference detection pixel A is configured as described above, and onlya part of the incident light enters into the light-receiving element 11.

The second phase difference detection pixel B includes a light-receivingelement 21. Also, a microlens 22 is provided on the incident side of thelight. Furthermore, a light-shielding layer 23 that blocks incidentlight is provided between the light-receiving element 21 and themicrolens 22 in order to perform pupil division. The light-shieldinglayer 23 has an opening 24 eccentric to one side direction with respectto the center of the light-receiving element.

The light-shielding layer 23 is configured to block a side opposite tothe direction blocked by the light-shielding layer 13 in the first phasedifference detection pixel A. As a result, the first phase differencedetection pixel A and the second phase difference detection pixel B areconfigured to block light on each opposite side with respect to adistance measurement direction. The second phase difference detectionpixel B is configured as described above, and only a part of theincident light enters into the light-receiving element 21.

The phase difference detection pixels configured as described above arearranged in the image capture element as illustrated in FIG. 3C. Byusing output from this phase difference detection pixel, it is possibleto perform so-called image plane phase-detection AF. Note that the phasedifference detection pixel may function only as a phase differencedetection pixel and may not function as a normal pixel, or, by composingone pixel with two independent photodiodes, the phase differencedetection pixel may also function as for image capture and phasedifference detection.

First, a first aspect of the autofocus control will be described withreference to FIG. 4. The first aspect is a case where detection in thevertical and horizontal directions can be performed by image planephase-detection AF. In the graph of FIG. 4, in a case where the verticalaxis is MTF and the horizontal axis is the amount of defocus in thevertical direction, an example of the MTF characteristics in thevertical direction and the MTF characteristics in the horizontaldirection when imaging the subject is illustrated. In image planephase-detection AF, it is possible to calculate a peak position of MTFcharacteristic in each of the vertical and horizontal directions as theamount of defocus. In FIG. 4, also, as described above, the anamorphiclens 101 has different peak positions between the vertical andhorizontal directions.

Since the image capture device 100 has one focus mechanism, even if thepeak positions between the vertical and horizontal directions aredifferent, it is necessary to determine any one of the in-focuspositions to be focused on. Therefore, in the present embodiment, thein-focus position is determined to be one by the following method.

After the in-focus position is determined, the lens driver 103 causesthe anamorphic lens 101 to operate under the control of the AF controlunit 152 on the basis of the in-focus position information to performautofocus.

Firstly, in a first method, a position corresponding to a mean amount ofdefocus between the amount of defocus corresponding to the peak positionof the MTF characteristic in the vertical direction and the amount ofdefocus corresponding to the peak position of the MTF characteristic inthe horizontal direction is set as the in-focus position. As a result,it is possible to set a position that is well-balanced with respect toboth of the vertical and horizontal directions as the in-focus position.

Also, in a second method, a position where a value P1 calculated by thefollowing evaluation formula [1] becomes the largest is set as thein-focus position. In this second method, the in-focus position is setto a position considering high MTF characteristics.

P1=MTF_(H)(focus)²+MTF_(V)(focus)²   [Formula 1]

Also, in a third method, a tilt component of the subject (a subjectangle is regarded as R) is added to the element for determining thein-focus position, and a position where a value P2 calculated by thefollowing evaluation formula [2] where the subject angle R is applied toFormula 1 of the second method described above becomes the largest isset as the in-focus position. Since the subject normally inclines in theimage, according to this third method that can determine the in-focusposition according to the inclination of the subject, it is possible toperform more precise autofocus control.

P2=(MTF_(H)(focus)·cos R)²+(MTF_(V)(focus)·sin R)²   [Formula 2]

Also, a fourth method is to determine a position on the basis of adegree of reliability of the detection results in the vertical andhorizontal directions. The degree of reliability will be described here.

Block matching is generally used for detection of phase-detection AF,and the sum of absolute difference (SAD) is one of the methods forcalculating the degree of similarity in block matching. In the SAD, “thesum of the absolute value of the differences between each pixel value”is an evaluation value for evaluating the degree of similarity. Theplace where the value becomes the smallest is the place where thesimilarity becomes the highest. Therefore, in a case where the SAD isequal to zero, the case means that the degree of reliability ofdetection is high, and the larger the value of the SAD, the lower thedegree of reliability.

Block matching is performed in each of the vertical and horizontaldirections to calculate the degree of reliability, and the peak positionhaving the higher degree of reliability in either the vertical orhorizontal direction is set as the in-focus position.

Also, in a fifth method, the vertical direction is prioritized, and thepeak position of the MTF characteristic in the vertical direction is setas the in-focus position. It is because, as described with reference toFIG. 2, in the anamorphic lens 101, the inclination of the MTFcharacteristic is different between the vertical and horizontaldirections, and the range of the amount of defocus where the MTF valuesare in the higher range is narrower in the vertical direction, thefocusing accuracy may be higher. Therefore, in the fifth method, thevertical direction is prioritized.

Furthermore, in a sixth method, the tilt component of the subject(similar to the subject angle R in the third method) is detected, andthe in-focus position is adjusted to either the vertical direction orthe horizontal direction depending on whether the subject angle R isgreater than or less than 45 degrees. In the present embodiment, in acase where the subject angle R is greater than 45°, the in-focusposition in the vertical direction is used, and in a case where thesubject angle R is less than 45°, the in-focus position in thehorizontal direction is used.

As described above, in the first aspect of the autofocus control, thereare the first to sixth methods described above. It is possible todetermine which method is to be used by the criteria illustrated in FIG.5 on the basis of whether the MTF characteristics are present or absentand whether the subject angle is present or absent.

In a case where the MTF characteristics are present, and the subjectangle can be obtained by calculation, it is good to use the thirdmethod. This third method is the most accurate method among the first tosixth methods.

Also, in a case where the MTF characteristics are present, and thesubject angle is not calculated or cannot be calculated, it is good touse the second method.

Also, in a case where the MTF characteristic is absent and the subjectangle can be obtained by calculation, it is good to use the sixthmethod.

Furthermore, in a case where the MTF characteristic is absent, and thesubject angle is not calculated or cannot be calculated, it is good touse any one of the first method, the fourth method, and the fifthmethod. Which one to use may be set by the user or may be set by defaultat the time of manufacturing the image capture device 100 or the signalprocessing device 150.

Note that it is also possible to obtain the final in-focus position byaveraging the in-focus positions determined by some of the first tosixth methods described above.

Also, the user may be able to select which of the first to sixth methodsis to be used. On that occasion, it is also possible to provide sceneinformation or the like suitable for each of the first to sixth methodsto the user.

Next, the second aspect of the autofocus control will be described withreference to FIG. 6 The second aspect is a case where image planephase-detection AF can perform detection only in the horizontaldirection. In this case, any one of the first, second, and third methodsamong the first to sixth methods in the first aspect described above isused. It is because the fourth to sixth methods cannot be used unless itis possible to perform detection in both vertical and horizontaldirections. Note that examples of the configuration that can performdetection only in the horizontal direction are, for example, a case thatAF pixels are arranged so as to detect only in the horizontal directionbecause the image quality will deteriorate if AF pixels are arranged soas to perform detection in both vertical and horizontal directions, acase that detection is performed only in the horizontal direction inorder to reduce the processing load, and the like.

In a case of using the first, second, or third method, the vertical MTFcharacteristics and peak position are required. Therefore, the verticalMTF characteristics and peak position are kept as set valuespreliminarily. After using the criteria described in FIG. 5 to determinewhich method to use among the first, second, and third methods, the MTFcharacteristics and peak position that are kept are used when performingthat method.

Note that, since the MTF characteristics and peak position changedepending on parameters, for example, the state of the anamorphic lens101 (such as zoom, focus, F value, and the like), image height, andsubject frequency, combinations of the corresponding MTF characteristicsand peak position for each parameter are kept as a table.

[1-4. Processing of Driving and Stopping Lens]

Next, the drive and stop processing of the anamorphic lens 101 in theautofocus control will be described with reference to the flowchart ofFIG. 7.

After determining the in-focus position by the process described above,first, in step S11, the driving of the anamorphic lens 101 is startedaccording to the autofocus control by the AF control unit 152. Thisstart of driving the anamorphic lens 101 is performed by the lens driver103 that causes the anamorphic lens 101 to operate under the control ofthe AF control unit 152.

Next, in step S12, it is determined by detection whether or not thevalue of the depth of field in the vertical direction is equal to orless than a predetermined value. This predetermined value is, forexample, 1. In this step S12, the depth of field in the verticaldirection is used, and the driving of the anamorphic lens 101 is notstopped even if the depth of field in the horizontal direction is equalto or less than a predetermined value. This is because, as describedwith reference to FIG. 2, in the anamorphic lens 101, the MTFcharacteristics tend to decrease in the vertical direction compared tothe horizontal direction, and the range of the amount of defocus whichis regarded to be in focus is narrow, it is possible to perform aprocess of stopping driving the lens linked with focusing moreaccurately by using the vertical direction as a reference.

In a case where the depth of field is not equal to or less than thepredetermined value, the process returns to step S12, and thedetermination in step S12 is repeated until the depth of field becomesequal to or less than the predetermined value (No in step S12).

Then, in a case where the depth of field becomes equal to or less than apredetermined value, the process proceeds to step S13 (Yes in step S12).In a case where the depth of field becomes equal to or less than apredetermined value, it can be said that the subject is in focus.Therefore, in step S13, the driving of the anamorphic lens 101 isstopped. This stop of driving the anamorphic lens 101 is performed bythe lens driver 103 that causes the anamorphic lens 101 to stop drivingunder the control of the AF control unit 152. Then, in step S14, anin-focus indication is displayed on the display unit 110 of the imagecapture device 100. As a result, the user can recognize that the subjectis in focus.

[1-5. Configuration of Image Capture Element]

Next, a configuration of the image capture element 300 that is optimalfor performing the processing described above will be described withreference to FIG. 8. In this description, the image capture element 300is the image capture element 300 provided with a phase differencedetection pixel 310 for image plane phase-detection AF. In FIG. 8, eachrectangular frame indicates a pixel of the image capture element 300,and a black rectangle indicates the phase difference detection pixel310.

As described above, the anamorphic lens 101 has different focal lengthsin the vertical and horizontal directions and generally has a shortfocal length in the horizontal direction. An image is recorded in astate that the image is compressed in the horizontal direction whenimaging, and it is possible to reproduce a horizontally long image bystretching the image in the horizontal direction when reproducing theimage. Therefore, as illustrated in FIG. 8, it is preferable that theimage capture element 300 also has different arrangement intervals ofthe phase difference detection pixels between the vertical direction andthe horizontal direction.

Since the anamorphic lens 101 has different focal lengths in thevertical and horizontal directions and generally has a shorter focallength in the horizontal direction, the phase difference detectionpixels are arranged to be sparser in the vertical direction than thehorizontal direction and denser in the horizontal direction than thevertical direction. It is because the image is recorded in a compressedstate in the horizontal direction, and it is necessary to sample thephase difference detection pixels more densely. Note that, regarding thearrangement intervals of the phase difference detection pixels in thevertical and horizontal directions illustrated in FIG. 8, thearrangement interval in the vertical direction is twice the arrangementinterval in the horizontal direction, but this is just an example, andthe present technology is not limited to the arrangement interval. Thedensity of the phase difference detection pixels in the horizontaldirection should be increased from the density in the vertical directionin accordance with the anamorphic ratio.

Depending on the frequency of the subject also, the MTF characteristicsin the vertical direction and the MTF characteristics in the horizontaldirection change and become different from each other. Even for the samesubject, the MTF characteristics differ between the vertical andhorizontal directions.

Therefore, in order to accurately acquire the MTF characteristics in thevertical and horizontal directions, it is desirable to configure theimage capture element 300 as illustrated in FIG. 8.

Note that, in addition to the phase difference detection pixels, it isalso possible to perform convolution and frequency characteristics of afilter for noise reduction of normal pixels according to the differencein focal lengths between the vertical and horizontal directions of theanamorphic lens 101.

Furthermore, in a case where the arrangement densities of the phasedifference detection pixels in the image capture element 300 are thesame between the vertical and horizontal directions, for example, it isalso possible to configure that the filter for noise reduction ischanged between the vertical and horizontal directions.

Also, as illustrated in FIG. 9, in an image capture element 400, a pupilpattern used in image plane phase-detection AF may be changed accordingto an exit pupil distance (EPD) in the vertical and horizontaldirections. The rows and columns of the phase difference pixelscorrespond to the exit pupil of the lens, and a light-shielding positionis modulated in an image height direction. In a case of a camera whoselens is interchangeable, since long and short exit pupils exist,detection is performed by selecting a row of phase difference pixels anda column of phase difference pixels appropriate for the lens. Varioustypes of rows of phase difference pixels and columns of phase differencepixels are referred to as pupil patterns. Since the anamorphic lens 101has different focal lengths between the vertical and horizontaldirections, the exit pupil distance may also differ between the verticaland horizontal directions in some cases. Therefore, in the image captureelement 400, the pattern of the pupil in the vertical direction is setto be different from the pattern of the pupil in the horizontaldirection. For example, as illustrated in FIG. 9, it is preferable toincrease the pattern of the pupil used in the horizontal direction fromthe vertical direction in accordance with the anamorphic ratio of theanamorphic lens 101.

Note that the image capture elements 300 and 400 described withreference to FIGS. 8 and 9 are not essential for autofocus in the imagecapture device 100 including the anamorphic lens 101 in the firstembodiment, but it is possible to improve the accuracy of autofocus byusing the image capture elements 300 and 400 configured as describedabove.

As described above, the image capture device 100 and the signalprocessing device 150 according to the first embodiment are configured.According to the first embodiment, it is possible to realize autofocuseven in the image capture device 100 provided with the anamorphic lens101.

Also, according to the first embodiment, since the autofocus is notrealized by a two-step process such as focusing in one of the verticaland horizontal directions and then focusing in the other direction, itis possible to perform autofocus at high speed even in the image capturedevice 100 provided with the anamorphic lens 101. Also, there is anadvantage that it is possible to realize autofocus in the image capturedevice 100 including the anamorphic lens 101 by using a small number ofparts.

2. Second Embodiment

[2-1. Configuration of Image Capture Device]

Next, a second embodiment of the present technology will be described.In the second embodiment, in an image capture device 200 including theanamorphic lens 101, by the detection process, an edge (a change inbrightness between adjacent pixels (contrast)) as characteristics in thevertical direction of the anamorphic lens 101 and as characteristics inthe horizontal direction of the anamorphic lens 101 is detected in eachof the directions, and the peaking process is performed on the basis ofthe edge.

Peaking is a process of detecting a high-frequency component in animage, identifying an in-focus portion of the subject, and emphasizingand displaying the pixels constituting the edge of the subject. Theprocess of emphasizing pixels that constitute the edge portion isperformed by drawing the pixels with markers in a predetermined color toincrease the lines along the edges of the subject or thickening thelines along the contour of the subject. Also, the process may beperformed by changing the brightness or color tone of the pixels orsuperimposing a signal for the emphasizing process on the pixels. It isalso possible to relatively reduce the brightness and color tone ofpixels other than the pixels to be emphasized so that the pixels otherthan the pixels to be emphasized are displayed blurred. If it ispossible to distinguish the pixels to be emphasized from other pixels,the enhancement method is not limited to a specific method.

As described with reference to FIG. 2, the anamorphic lens 101 hasdifferent MTF characteristics between the vertical and horizontaldirections, and the MTF value is less likely to decrease in thehorizontal direction. Therefore, since the MTF values are in the higherrange and the range of the amount of defocus, which is regarded to be infocus, is wider in the horizontal direction compared to the verticaldirection, there is a possibility that the emphasizing process byaccurate peaking cannot be performed if the peaking process in thevertical and horizontal directions is performed by the same process insome cases. Therefore, in the second embodiment, edges are detected bythe detection process in each of the vertical and horizontal directionsof the image corresponding to each of the vertical and horizontaldirections of the anamorphic lens 101 to perform the peaking process.

A configuration of the image capture device 200 including a peakingprocessing unit 210 as a signal processing device according to thesecond embodiment will be described with reference to FIG. 10.

The image capture device 200 includes an optical image capture system102 including an anamorphic lens 101, a lens driver 103, an imagecapture element 104, a signal processing LSI 105, an image signalprocessing unit 106, a codec unit 107, a storage unit 108, a displaycontrol unit 109, a display unit 110, an input unit 111, a control unit112, and a peaking processing unit 210 as a signal processing device.The same configurations as in the first embodiment are designated by thesame signs, and the description thereof will be omitted.

A configuration of the peaking processing unit 210 will be describedwith reference to FIG. 11. The peaking processing unit 210 separatelyperforms the peaking process in each of the vertical and horizontaldirections of the image. It is because the anamorphic lens 101 hasdifferent focal lengths between the vertical and horizontal directions,so it is appropriate to perform the peaking process individually in thevertical direction and the horizontal direction.

Peaking settings for performing peaking include a band of a filter 212having a predetermined filter coefficient for extracting high-frequencycomponents from the image and a reaction sensitivity for detecting apeak signal by comparing with the energy of the high-frequencycomponents in the image. The reaction sensitivity is adjusted by raisingor lowering a gain or a peaking threshold of the filter 212. To raisethe reaction sensitivity, raise the gain or lower the peaking thresholdof the filter 212. To lower the reaction sensitivity, lower the gain orraise the peaking threshold of the filter 212. Hereinafter, theadjustment of the reaction sensitivity will be described as beingperformed by raising or lowering the peaking threshold.

The peaking processing unit 210 performs the emphasizing process bypeaking in a case where the energy of the high-frequency component inthe image exceeds the peaking threshold. In this peaking, thehigh-frequency component extraction process by the filter 212 having apredetermined filter coefficient, the comparison process between theenergy of the extracted high-frequency component and the peakingthreshold, and the drawing process that emphasizes the pixels whoseenergy of the high-frequency component is determined to be larger thanthe peaking threshold. In order to perform peaking with high accuracy,it is necessary to extract high-frequency components by the filter 212as much as possible. By performing peaking, it is possible to emphasizea subject that is in focus in the image. Therefore, the user can easilyperform focusing by focusing on the image so that the number ofemphasized points due to peaking increases.

The peaking processing unit 210 includes a noise removing unit 211, afilter 212, a peak detection unit 213, a drawing unit 214, and an areacomparison unit 215.

The noise removing unit 211 sets a threshold value for removing noisefor energy in the image, removes low-level edge components, removeshigh-frequency component noise, and the like.

The filter 212 is, for example, a high-pass filter having apredetermined filter coefficient, and the filter 212 identifies the areain the image where the subject is in focus (focusing area) by detectingan edge, that is a high-frequency component of the image and is a changein brightness between adjacent pixels (contrast). This processcorresponds to edge detection by the detection process. The band of thefilter as the peaking setting described above is the band of the filter212.

The peak detection unit 213 compares the peaking threshold with theenergy of the high-frequency component of the image and detects a peaksignal that is equal to or higher than the peaking threshold. Thepeaking threshold as the peaking setting described above is a thresholdvalue used for detecting the peak signal in the peak detection unit 213.

The drawing unit 214 performs a peaking process for emphasizing a pixelwhose energy of the high-frequency component is determined to be largerthan the peaking threshold by comparison with the peaking threshold. Inthe present technology, the drawing process emphasizes the in-focusportion of the subject by detecting the high-frequency component in theimage, identifying the in-focus portion of the subject, and drawing amarker on the pixels constituting the edge of the subject.

The area comparison unit 215 performs a process of comparing the size ofan area in which the subject is in focus in the image in each of thevertical and horizontal directions supplied from the filter 212. Thearea comparison result is supplied to the drawing unit 214. On the basisof this area comparison result, the drawing unit 214 performs thedrawing process so as to make a difference in the degree of emphasisbetween the area in focus in the vertical direction and the area infocus in the horizontal direction.

Note that the peaking processing unit 210 as a signal processing deviceincludes a program, and the program may be installed in the imagecapture device 200 preliminarily or may be distributed by download,storage medium, or the like so that the user may install the program byhimself/herself. Note that the peaking processing unit 210 is not onlyrealized by a program but may also be realized by combining a dedicateddevice, a circuit, or the like by hardware having the function.

[2-2. Peaking Process]

Next, the peaking process in the second embodiment will be describedwith reference to FIGS. 12 and 13. There are first to fifth methods forthe peaking process. FIG. 13 also illustrates an aspect of anemphasizing process of the conventional general peaking process as acomparative example.

In FIGS. 12 and 13, the subject to be focused on is a circular objectfrom the viewpoint of easy-understanding of the emphasizing process thatperforms peaking in the vertical and horizontal directions. Then,portions emphasized by peaking are illustrated with slant lines. Also,the number of slant lines indicates the strength (degree) of emphasis onpeaking.

Also, for convenience of explanation, it is assumed that the peakpositions of focus in the vertical and horizontal directions (MTF peaks)are almost the same. Also, it is assumed that the depth of field in thehorizontal direction is deep and the depth of field in the verticaldirection is shallower than the depth of field in the horizontaldirection. Also, it is assumed that the vertical direction of theanamorphic lens 101 and the vertical direction of the image correspondto each other and match the direction and the horizontal direction ofthe anamorphic lens 101 and the horizontal direction of the imagecorrespond to each other and match the direction.

In the first method, the emphasizing process by peaking is performed onan area that is in focus in each of the vertical direction and thehorizontal direction. Therefore, in a case where the subject is in focusin the vertical direction and also the subject is in focus in thehorizontal direction (within the depth of field in both of the verticaland horizontal directions), the emphasizing process by peaking isperformed on the area where being in-focus in both of the vertical andhorizontal directions.

Also, in this first method, in a case where being out of the depth offield in the vertical direction and also within the depth of field in afront focus state, the emphasizing process by peaking is performed onlyin the horizontal direction. Also, in the first method, in a case wherebeing out of the depth of field in the vertical direction and alsowithin the depth of field in the horizontal direction in a back focus,the emphasizing process by peaking is performed only in the horizontaldirection.

Note that the front focus refers to a state in which another subject infront of the main subject to be imaged by the user is in focus. Also,the back focus refers to a state in which the main subject to be imagedby the user is out of focus and another subject behind is in focus.

In this first method, the area comparison unit 215 does not need tocompare the areas that are in focus in the vertical and horizontaldirections.

In the second method, the emphasizing process by peaking is performedonly in either the vertical direction or the horizontal directionwhichever has a narrower area being in focus. Therefore, in a case wherethe in-focus area in the vertical direction is narrower than thein-focus area in the horizontal direction, the emphasizing process bypeaking is performed only in the vertical direction. In the front focusstate and the back focus state, the emphasizing process by peaking isnot performed.

In this second method, the area comparison unit 215 compares which areabeing in focus in the vertical direction or the horizontal direction isnarrower and supplies the comparison result to the drawing unit 214.Then, the drawing unit 214 performs the drawing process only in eitherthe vertical direction or the horizontal direction in which the areabeing in focus is narrower.

In the third method, in either the vertical direction or the horizontaldirection, the emphasizing process is performed strongly in thedirection in which the area being in focus is narrower, and theemphasizing process is performed weakly in the direction in which thearea being in focus is wider. For example, in a case where the areabeing in focus in the vertical direction is narrower than the area beingin focus in the horizontal direction, the emphasizing process isperformed strongly on the area being in focus in the vertical direction.On the other hand, the emphasizing process is performed weakly on thearea being in focus in the horizontal direction.

In this third method, the area comparison unit 215 compares which areabeing in focus in the vertical direction or the horizontal direction isnarrower and supplies the comparison result to the drawing unit 214.Then, in either the vertical direction or the horizontal direction, thedrawing unit 214 performs the drawing process so as to stronglyemphasize the direction in which the area being in focus is narrower andperforms the drawing process so as to weakly emphasize the direction inwhich the area being in focus is wider. The strong emphasizing processand the weak emphasizing process include, for example, a difference inthe number of lines along the edge of the subject, a difference in thethickness of lines along the contour of the subject, and the like.

As illustrated in FIG. 13, the fourth method detects an area being infocus in either one direction of the vertical direction or thehorizontal direction, corrects the area being in focus from opticalinformation in the other direction, and performs the emphasizingprocess. Here, the optical information is information regarding a depthof field, and more specifically, is an F value. In a case of detectingan area being in focus only in the horizontal direction, since the depthof field in the horizontal direction is wider than the depth of field inthe vertical direction, the emphasizing and displaying process isperformed only in the horizontal direction as in the conventional methodillustrated in FIG. 13. However, considering the depth of field in boththe vertical and horizontal directions, it is possible to display thearea being in focus better rather by performing the displaying processin the direction in which the area being in focus is narrower as in thesecond method in FIG. 12. Therefore, by displaying the depth areadetected in the horizontal direction by narrowing the area by, forexample, the ratio of the F values in the vertical and horizontaldirections, as illustrated in FIG. 13, it is possible to emphasize anddisplay the direction in which the area being in focus is narrower.

The fifth method is to change a method of emphasizing peaking (color,shape, number of lines, thickness, and the like) each in the verticaldirection and the horizontal direction to perform the emphasizingprocess and let the user select where to focus.

As described above, the second embodiment of the present technology isconfigured. According to this second embodiment, even in the imagecapture device 200 including the anamorphic lens 101 having differentfocal lengths each in the vertical direction and the horizontaldirection, it is possible to perform the peaking process appropriately.

Note that the user may be able to select which of the first to fifthmethods described above is used for the peaking process.

Also, the peaking process of the second embodiment can be used in a liveviewing when both imaging a still image and imaging a moving image.

Third Embodiment

[3-1. Configuration of Image Capture Device]

Next, a third embodiment of the present technology will be described.The third embodiment is different from the first embodiment in that thesignal processing device 150 performs the focus adjustment process. FIG.14 is a block diagram illustrating a configuration of an image capturedevice 100 according to the third embodiment. Since the configuration ofthe image capture device 100 other than the signal processing device 150is similar to the configuration of the first embodiment, the descriptionthereof will be omitted. The signal processing device 150 performs afine focus adjustment process and focus bracket imaging processdescribed below on the basis of a predetermined parameter of the imagecapture device 100.

[3-2. First Focus Adjustment Process by Signal Processing Device: FineFocus Adjustment]

A first aspect of the second embodiment is the fine focus adjustmentprocess in the image capture device 100 including the anamorphic lens101.

Fine focus adjustment is a function that when the user changes anadjustment amount set corresponding to the focus position, for example,by increasing by one or decreasing by one, by changing the focusposition (in-focus position) according to the change in the value, theuser can adjust the focus position manually. The image capture device100 of the present embodiment has this fine focus adjustment function.

A flow of the fine focus adjustment process in the signal processingdevice 150 will be described with reference to FIG. 15. First, in stepS301, a focus adjustment amount P1 changed by the user is acquired.

Next, in step S302, a fine focus adjustment amount is calculated usingFormula 3 below.

Fine focus adjustment amount=P1·√(horizontal F value×vertical Fvalue)×d3   [Formula 3]

The parameter d3 in Formula 3 is a constant for determining theallowable focus width. Note that [Formula 3] takes the geometric mean inthe horizontal and vertical directions, but it is not limited to this,and there is also a method of calculating with an arithmetic mean or aweighted mean that is weighted in the horizontal direction/verticaldirection.

Then, in step S303, a final amount of focus deviation for driving thelens for autofocus is calculated using Formula 4 below. The “calculatedamount of focus deviation” in Formula 4 is the amount of focus deviationwith respect to the in-focus position calculated in autofocus.

Final amount of focus deviation=Calculated amount of focusdeviation+Fine focus adjustment amount   [Formula 4]

Then, in step S304, the anamorphic lens 101 is driven by the lens driver103 on the basis of the final amount of focus deviation calculated instep S303 to finely adjust the focus.

The first aspect of processing in the signal processing device 150 isconfigured as described above. According to the first aspect of thethird embodiment, the user can use the function of adjusting focusfinely even in the image capture device 100 provided with the anamorphiclens without any special operation or handling.

[3-3. Second Focus Adjustment Process by Signal Processing Device: FocusBracket Imaging]

Next, a second aspect of processing in the signal processing device 150of the third embodiment will be described. The second aspect is a focusbracket (also referred to as a focus bracket) imaging process in theimage capture device 100 including the anamorphic lens 101.

Focus bracket imaging is a function that images continuously untilfinishing capturing a set number of images while moving the focusposition with a preset amount of focus bracket by one shutter operation.All captured images have different focus positions. More specifically, aplurality of images is captured by shifting from the in-focus positionas a center by the amount of focus deviation for each imaging. Forexample, in a case where the amount of bracket is b and the number ofimages to be captured is five, images are captured as follows.

First image: amount of b×2 from the in-focus position, front focus

Second image: amount of b×1 from the in-focus position, front focus

Third image: in-focus position

Fourth image: amount of b×1 from the in-focus position, back focus

Fifth image: amount of b×2 from the in-focus position, back focus

A flow of the focus bracket imaging process by the signal processingdevice 150 will be described with reference to FIG. 16. First, in stepS401, an amount of focus bracket P2 and the number of images to becaptured set by the user are acquired. These parameters can be obtainedfrom the setting information of the focus bracket of the image capturedevice 100.

Next, in step S402, the amount of focus bracket used in actual imagingis calculated using Formula 5 below.

Amount of focus bracket=P2·√(horizontal F value×vertical F value)×d5  [Formula 5]

The parameter d5 in Formula 5 is a constant for determining theallowable focus width and is a value determined according to a pixelpitch such as, for example, “a value obtained by a predetermined numberof times the minimum unit of a pixel” and the like. Note that [Formula5] takes the geometric mean in the horizontal and vertical directions,but it is not limited to this, and there is also a method of calculatingwith an arithmetic mean or a weighted mean that is weighted in thehorizontal direction/vertical direction.

Then, in step S403, under the control of the signal processing device150, by causing the anamorphic lens 101 to operate by the lens driver103 according to the amount of focus bracket, focus bracket imaging isperformed according to the amount of focus bracket and the number ofimages to be captured.

As described above, the third embodiment of the present technology isconfigured. According to this third embodiment, even in the imagecapture device 100 provided with an anamorphic lens, without any specialtreatment, it is possible to use fine focus adjustment and the focusbracket imaging function, which are the functions provided in anordinary camera.

The second aspect of the processing in the signal processing device 150is configured as described above. According to the second aspect of thethird embodiment, the user can use the function of focus bracket imagingeven in the image capture device 100 provided with the anamorphic lenswithout any special operation or handling.

As described above, the third embodiment of the present technology isconfigured. According to this third embodiment, even in the imagecapture device 100 provided with an anamorphic lens, without any specialtreatment, it is possible to use the fine focus adjustment function andfocus bracket imaging function, which are the functions provided in anordinary camera.

4. Modification example

Although the embodiments of the present technology have beenspecifically described above, the present technology is not limited tothe above-described embodiments, and various types of modificationsbased on the technical idea of the present technology are possible.

It is possible to apply the first embodiment to any of thephase-detection AF method, the contrast AF method, and the image planephase-detection AF method.

In the second embodiment, it has been described that the peakingprocessing unit 210 performs the peaking process separately for each ofthe vertical direction and the horizontal direction of the image, but itis also possible to provide a first peaking processing unit for thevertical direction and a second peaking processing unit for thehorizontal direction.

The present technology may also be configured as below.

(1)

A signal processing device that, on the basis of an image capture signalacquired by an image capture device provided with an anamorphic lens,performs a detection process each in a vertical direction of theanamorphic lens and in a horizontal direction of the anamorphic lens.

(2)

The signal processing device according to (1), in which the signalprocessing device determines an in-focus position on the basis of acharacteristic in the vertical direction of the anamorphic lens and acharacteristic in the horizontal direction of the anamorphic lensacquired by the detection process.

(3)

The signal processing device according to (2), in which thecharacteristic is an MTF characteristic, which is represented by an MTFvalue and an in-focus position which is represented by an amount ofdefocus in the vertical direction of the anamorphic lens.

(4)

The signal processing device according to (2) or (3), in which thesignal processing device determines the in-focus position on the basisof an average of the amount of defocus corresponding to a peak of theMTF characteristic in the vertical direction of the anamorphic lens andthe amount of defocus corresponding to a peak of the MTF characteristicin the horizontal direction of the anamorphic lens.

(5)

The signal processing device according to any one of (2) to (4), inwhich the signal processing device determines a position where a valuecalculated from a first evaluation formula is maximized as the in-focusposition by using the MTF characteristic in the vertical direction ofthe anamorphic lens and the MTF characteristic in the horizontaldirection of the anamorphic lens.

(6)

The signal processing device according to any one of (2) to (5), inwhich the signal processing device determines a position where a valuecalculated from a second evaluation formula is maximized as the in-focusposition by using the MTF characteristic in the vertical direction ofthe anamorphic lens, the MTF characteristic in the horizontal directionof the anamorphic lens, and tilt information of a subject.

(7)

The signal processing device according to any one of (2) to (6), inwhich the signal processing device determines the in-focus position onthe basis of a degree of reliability of the detection.

(8)

The signal processing device according to (7), in which the degree ofreliability is an evaluation value of a block matching process performedeach in the vertical direction and in the horizontal direction as thedetection process.

(9)

The signal processing device according to any one of (2) to (8), inwhich the signal processing device determines a focus adjustment methodon the basis of whether an MTF characteristic is present or absent andwhether information regarding an angle of a subject is present orabsent.

(10)

The signal processing device according to (1), in which the signalprocessing device performs a peaking process on the basis of acharacteristic in the vertical direction of the anamorphic lens and acharacteristic in the horizontal direction of the anamorphic lensacquired by the detection process.

(11)

The signal processing device according to (10), in which thecharacteristic is a change in brightness between adjacent pixels.

(12)

The signal processing device according to (10) or (11), in which thesignal processing device performs a peaking process on an area in theimage being in focus in the vertical direction and an area in the imagebeing in focus in the horizontal direction.

(13)

The signal processing device according to any one of (10) to (12), inwhich the signal processing device performs the peaking process only onan area being narrower, between the area in the image being in focus inthe vertical direction and the area in the image being in focus in thehorizontal direction.

(14)

The signal processing device according to any one of (10) to (13), inwhich the signal processing device performs the peaking process so as toemphasize an area being narrower than an area being wider, between thearea in the image being in focus in the vertical direction and the areain the image being in focus in the horizontal direction.

(15)

The signal processing device according to (1), in which the signalprocessing device performs a focus adjustment process in the imagecapture device on the basis of an in-focus position determined by thedetection process and a predetermined parameter.

(16)

The signal processing device according to (15), in which the signalprocessing device performs a focus adjustment process on the basis of anF value in a direction corresponding to the vertical direction of theanamorphic lens and an F value in a direction corresponding to thehorizontal direction of the anamorphic lens as the predeterminedparameters.

(17)

The signal processing device according to (15) or (16), in which thesignal processing device sets an amount of focus bracket in a focusbracket imaging, as the focus adjustment process, on the basis of the Fvalue in the direction corresponding to the vertical direction of theanamorphic lens and the F value in the direction corresponding to thehorizontal direction of the anamorphic lens as the predeterminedparameter.

(18)

A signal processing method including performing a detection process, onthe basis of an image capture signal acquired by an image capture deviceprovided with an anamorphic lens, each in a vertical direction of theanamorphic lens and in a horizontal direction of the anamorphic lens.

(19)

A signal processing program for, on the basis of an image capture signalacquired by an image capture device provided with an anamorphic lens,causing a computer to execute a signal processing method includingperforming a detection process each in the vertical direction of theanamorphic lens and in the horizontal direction of the anamorphic lens.

(20)

An image capture device including:

an anamorphic lens;

an image capture element that is provided with a plurality of phasedifference detection pixels arranged to make placement densitiesdifferent between a direction corresponding to a vertical direction ofthe anamorphic and a direction corresponding to a horizontal directionorthogonal to the vertical direction of the anamorphic lens; and

a signal processing unit that performs a detection process each in thevertical direction of the anamorphic lens and in the horizontaldirection of the anamorphic lens on the basis of an image capture signalacquired by the image capture element.

(21)

The image capture device according to (20), in which the image capturedevice performs autofocus control on the basis of an in-focus positiondetermined by the detection process.

REFERENCE SIGNS LIST

-   100, 200 Image capture device-   104 Image capture element-   150 Signal processing device-   210 Peaking processing unit

1. A signal processing device that, on a basis of an image capture signal acquired by an image capture device provided with an anamorphic lens, performs a detection process each in a vertical direction of the anamorphic lens and in a horizontal direction of the anamorphic lens.
 2. The signal processing device according to claim 1, wherein the signal processing device determines an in-focus position on a basis of a characteristic in the vertical direction of the anamorphic lens and a characteristic in the horizontal direction of the anamorphic lens acquired by the detection process.
 3. The signal processing device according to claim 2, wherein the characteristic is an MTF characteristic, which is represented by an MTF value and an in-focus position which is represented by an amount of defocus in the vertical direction of the anamorphic lens.
 4. The signal processing device according to claim 2, wherein the signal processing device determines the in-focus position on a basis of an average of the amount of defocus corresponding to a peak of the MTF characteristic in the vertical direction of the anamorphic lens and the amount of defocus corresponding to a peak of the MTF characteristic in the horizontal direction of the anamorphic lens.
 5. The signal processing device according to claim 2, wherein the signal processing device determines a position where a value calculated from a first evaluation formula is maximized as the in-focus position by using the MTF characteristic in the vertical direction of the anamorphic lens and the MTF characteristic in the horizontal direction of the anamorphic lens.
 6. The signal processing device according to claim 2, wherein the signal processing device determines a position where a value calculated from a second evaluation formula is maximized as the in-focus position by using the MTF characteristic in the vertical direction of the anamorphic lens, the MTF characteristic in the horizontal direction of the anamorphic lens, and tilt information of a subject.
 7. The signal processing device according to claim 2, wherein the signal processing device determines the in-focus position on a basis of a degree of reliability of the detection.
 8. The signal processing device according to claim 7, wherein the degree of reliability is an evaluation value of a block matching process performed each in the vertical direction and in the horizontal direction as the detection process.
 9. The signal processing device according to claim 2, wherein the signal processing device determines a focus adjustment method on a basis of whether an MTF characteristic is present or absent and whether information regarding an angle of a subject is present or absent.
 10. The signal processing device according to claim 1, wherein the signal processing device performs a peaking process on a basis of a characteristic in the vertical direction of the anamorphic lens and a characteristic in the horizontal direction of the anamorphic lens acquired by the detection process.
 11. The signal processing device according to claim 10, wherein the characteristic is a change in brightness between adjacent pixels.
 12. The signal processing device according to claim 10, wherein the signal processing device performs a peaking process on an area in the image being in focus in the vertical direction and an area in the image being in focus in the horizontal direction.
 13. The signal processing device according to claim 10, wherein the signal processing device performs the peaking process only on an area being narrower, between the area in the image being in focus in the vertical direction and the area in the image being in focus in the horizontal direction.
 14. The signal processing device according to claim 10, wherein the signal processing device performs the peaking process so as to emphasize an area being narrower than an area being wider, between the area in the image being in focus in the vertical direction and the area in the image being in focus in the horizontal direction.
 15. The signal processing device according to claim 1, wherein the signal processing device performs a focus adjustment process in the image capture device on a basis of an in-focus position determined by the detection process and a predetermined parameter.
 16. The signal processing device according to claim 15, wherein the signal processing device performs a focus adjustment process on a basis of an F value in a direction corresponding to the vertical direction of the anamorphic lens and an F value in a direction corresponding to the horizontal direction of the anamorphic lens as the predetermined parameters.
 17. The signal processing device according to claim 15, wherein the signal processing device sets an amount of focus bracket in a focus bracket imaging, as the focus adjustment process, on a basis of the F value in the direction corresponding to the vertical direction of the anamorphic lens and the F value in the direction corresponding to the horizontal direction of the anamorphic lens as the predetermined parameters.
 18. A signal processing method comprising performing a detection process, on a basis of an image capture signal acquired by an image capture device provided with an anamorphic lens, each in a vertical direction of the anamorphic lens and in a horizontal direction of the anamorphic lens.
 19. A signal processing program for, on a basis of an image capture signal acquired by an image capture device provided with an anamorphic lens, causing a computer to execute a signal processing method including performing a detection process each in a vertical direction of the anamorphic lens and in a horizontal direction of the anamorphic lens.
 20. An image capture device comprising: an anamorphic lens; an image capture element that is provided with a plurality of phase difference detection pixels arranged to make placement densities different between a direction corresponding to a vertical direction of the anamorphic and a direction corresponding to a horizontal direction orthogonal to the vertical direction of the anamorphic lens; and a signal processing unit that performs a detection process each in the vertical direction of the anamorphic lens and in the horizontal direction of the anamorphic lens on a basis of an image capture signal acquired by the image capture element.
 21. The image capture device according to claim 20, wherein the image capture device performs autofocus control on a basis of an in-focus position determined by the detection process. 